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Safety Shut-off Valves

Safety shut-off valves (SSOVs) are the primary automatic means of turning gas flow ON and OFF for furnaces, ovens, and in some cases, individual burners (keep in mind that a "manual shut-off valve" is always required). SSOVs are required by national codes and standards with at least two SSOVs required between a burner and the fuel supply. Besides that, they are a good way of keeping you and your factory from joining the upper atmosphere.

In conjunction with "code-required safety circuits", the SSOVs automatically close in the event of a detected hazardous condition.


  • are required to close in less than one second
  • have an effective leakage rate of 0 (it's actually a really, really small number)
  • include visual indication (a means of showing if they are opened or closed)
  • usually include a means of electrically proving closure (either a "proof of closure switch" or a "leak-detection/tightness control" system)

SSOVs can incorporate additional features making them useful for

  • reducing system pressure (like the VAD)
  • automatically matching gas pressure to an impulse pressure (like the VAG)
  • "pulse-firing" applications requiring high duty cycles
Safety Shut-off Valve VAS

Safety Shut-off Valve VAS
Solenoid Valve VAS is designed for safeguarding and controlling the air and gas supply to gas burners and gas appliances.

Gas/Air Ratio Control with Solenoid Valve VAG

Safety Shut-off Valve VAG
Gas/Air ratio control with solenoid valve VAG maintains a constant air/gas pressure ratio for modulating-controlled burners or with VAS 1 bypass valve for stage-controlled burners

Gas Regulator with Solenoid Valve VAD

Safety Shut-off Valve VAD
The gas regulator with solenoid valve VAD with high control accuracy, is for excess air burners, atmospheric burners, or single-stage forced air burners. Pressure preset via setpoint spring.

Gas Pressure Regulator with Overpressure Shut-off Valve JSAV

Gas Pressure Regulator with Overpressure Shut-off Valve JSAV

Use the JSAV regulator to protect against high pressure for valves downstream from a gas regulator.

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